Improvement in mechanisms for operating the thread-guide in wax-thread sewing



UNITED STATES PATENT QFFICE ALBERT e. BREWER, 0E EoPKINTON, MASSACHUSETTS.

IMPROVEMENT IN MECHANISMS FOR OPERATING THE THREAD-GUIDE IN WAX THREAD SEWING- MACHINES.

Specification forming part of Letters Patent No. l52,894, dated July 14, 1874; application filed December 12, 1873.

To all whom it may concern:

Be it known that I, ALBERT G. BREWER, of Hopkinton, State of Massachusetts, have invented Means for Operating the Thread- Guide for Leather-Stitching and Siding Machines, of which the following is a specification:

The object of my invention is to operate the thread-guide in a wax thread sewing-machine; and it consists in a threadguide provided with a twisted cam-surface, combined with a spring-stud and roll, operating the same as hereinafter described.

Figure 1 represents the cam and grooved roll when in the stitching or siding machine, A being the cam; B, the grooved roll; 0, the spring-stud, 011 which the roll revolves; D, the set-screw that presses against the spring-stud and carrying the roll against the cam.

The operation is this: \Vhen the arm E is made to move, the thread guide roll B moves up and down 011 the flat surface I of the cam A, and, as the roll B nears the top of the cam, its surface being twisted, turns the cam, carrying with it the thread-guide F, as desired. As the spring-stud becomes weakened by constant use, the roll B can be pressed against the cam more firmly by turning the set-screw D.

I claim as my invention- The thread-guide cam A, having the twisted surface I, combined with the spring stud G and roller B, when constructed and operated as and for the purpose described.

ALBERT G. BREWER.

Witnesses L. H. WAKEFIELD, CYRUS A. BREWER. 

